Vascular access device

ABSTRACT

A vascular access device having a spring-biased septum is provided for preventing the leakage of blood during the placement and use of vascular catheters and similar devices. The structure of the device includes a housing with an internal channel. A spring-biased septum is placed securely within the channel such that it substantially blocks blood flow through the channel. The spring-biased septum includes an elastic plug having a pre-slit or pre-molded hole and a biasing element disposed about the elastic plug. A needle or other object may be withdrawn through the slit or hole, after which the biasing element forces the hole closed, preventing blood leakage.

BACKGROUND

[0001] This application is a continuation of application Ser. No.10/320,274, filed Dec. 16, 2002, which is a continuation of applicationSer. No. 09/819,490, filed Mar. 28, 2001, which is a continuation ofapplication Ser. No. 09/145,449 filed Sep. 2, 1998, now U.S. Pat. No.6,228,060.

THE FIELD OF THE INVENTION

[0002] The present invention is related to a blood seal having aspring-biased septum for use in connection with various medical devices.More specifically, the present invention relates to a blood seal havinga spring-biased septum which is particularly adaptable for use insealing a vascular access device immediately following placement of acatheter into a blood vessel of a patient.

TECHNICAL BACKGROUND

[0003] During medical treatment, patients often require medication,blood, or fluids. The most efficient way of administering thesesubstances is by depositing them directly into a patient's blood streamwhere the circulatory system quickly directs the substance to the targettissue or organ. Thus, vascular catheters for infusion of fluids, blood,and medications into patients are among the most commonly used medicaldevices. The insertion of a vascular catheter allows repeated orcontinuous access to the circulatory system of a patient. Vascularcatheters are generally inserted into the extremities of a patient andfluids, blood, and medications are introduced to the patient throughsuch catheters.

[0004] Catheters of this type are generally inserted into a vein orartery by means of an introducer needle. In one common configuration,the catheter is initially placed over the needle. The needle, with thecatheter located over the needle, is inserted into the patient until thedesired vein or artery is located. Once the needle and catheter areproperly located in the vein or artery, the needle is withdrawn from thecatheter and discarded. The catheter remains in the vein or artery toprovide access to the circulatory system of the patient without repeatedneedle punctures.

[0005] When the catheter insertion and placement steps have beenconcluded, one end of a tube (or “tubing set”) is generally attached tothe proximal end of the catheter. The opposite end of the tube isattached to a source of fluid and medication. The source of fluid istypically a bottle or bag containing the fluid required for treatment ofthe patient. Once attachment of the catheter to the fluid source iscompleted, fluids are allowed to flow through the tubing, into thecatheter, and ultimately into the patient. In most situations, fluidsflow through the tubing set and into the patient by means of gravityfeed or using a standard infusion pump.

[0006] It will be appreciated that it is important to minimize theleakage of blood to the outside environment during each of the stepsdescribed above. Blood leakage can expose medical personnel and othersto blood-borne diseases such as AIDS and hepatitis. Blood leakage cancontaminate equipment and supplies in the treatment area. Blood leakagemay also cause unnecessary alarm on the part of the patient and otherobservers. Thus, it is important to prevent or minimize blood leakage inorder to maintain safety, aesthetics, and to retain equipment andsupplies in good working order.

[0007] The placement and use of catheters of the type described aboveinvolve the potential for blood leakage. For example, the removal of theintroducer needle once the catheter is in place generally results in ashort period of time during which blood may flow out of the catheter tothe surrounding environment.

[0008] Attempts have been made to deal with the problem of blood leakageduring the placement of catheters. Many of these solutions employ latexor polyisoprene barriers that restrict blood flow. Such a barrier issituated so that after venipuncture and introduction of the catheterinto the blood vessel of a patient, the introducer needle is withdrawnthrough the barrier or plug. Unfortunately, most polymers, includingthose used in blood barriers, tend to take a set over time, especiallyif an object such as a needle, wire, or cannula remains in the plug fora prolonged period before use. As a result, when the needle is withdrawnthrough the barrier, the hole left by the needle may fail to reseal,allowing blood to leak from the device.

[0009] Other attempts to deal with the problem of blood leakagetypically involve devices that are expensive and complex to operate. Forexample, one such device employs a relatively complex valve mechanismconnected to the proximal end of the catheter which opens when a needleis inserted and then closes when the needle is removed. The valve thenopens again when the tubing set is attached to the catheter. This devicerequires a mechanism for repeated opening and closing of the valve, aswell as other collateral structures which facilitate operation of thedevice. These relatively complex structures complicate the device andadd to its cost. In addition, the valve device is designed to remain inplace after the tubing set is attached. This increases the potential forirritation and discomfort to the patient. Such devices are also tooexpensive for wide use in developing countries, where the problem of HIVinfection is growing and the need for cost-effective solutions is great.

[0010] Accordingly, it would be an advancement in the art to provide adevice which would control the flow of blood during the stepssurrounding placement and use of a catheter. It would also be anadvancement in the art to provide such a device which is inexpensive andsimple to operate. It would also be an advancement in the art to providesuch a device which could be used without requiring significantmodification of conventional catheters, needles, tubing sets and thelike. Finally, it would be a significant advancement in the art toprovide such a device which provided the medical professional with morecontrol in performing the tasks surrounding placement and use of acatheter.

[0011] Such apparatus are disclosed and claimed herein.

BRIEF SUMMARY AND OBJECTS OF THE INVENTION

[0012] The present invention is a blood seal having a spring-biasedseptum for preventing the leakage of blood during the placement and useof vascular catheters and similar devices. In one presently preferredembodiment, the blood seal has a housing, at least part of which issubstantially cylindrical in configuration. An internal channel throughthe housing is provided. A spring-biased septum is disposed within andsubstantially blocks the internal channel. In certain preferredembodiments, the spring-biased septum includes a formed elastic plugwith a pre-slit or pre-molded hole. In certain preferred embodiments,the elastic plug may be formed of a biocompatible elastomer such aslatex or polyisoprene.

[0013] In certain preferred embodiments, the elastic plug includes anannular groove in which a biasing element sits. The biasing element isdisposed about the elastic plug and keeps the slit or hole closed with apredictable force. In certain preferred embodiments of the presentinvention, the biasing element is a C-shaped spring constructed of ametal or metal alloy. In certain especially preferred embodiments, thebiasing element is a C-shaped spring constructed of spring steel.

[0014] It will be appreciated that the biasing element prevents bloodflow through the hole or slit, while the elastic plug prevents bloodfrom flowing around the spring-biased septum. In certain embodiments,the housing may be constructed of a soft elastomer. In such embodiments,the spring-biased septum may optionally include a rigid plug retainerthat surrounds and radially compresses at least part of the length ofthe elastic plug, thereby preventing leakage between the plug and thehousing. In other embodiments, the housing is constructed of more rigidmaterial, eliminating the need for a rigid plug retainer.

[0015] In certain preferred embodiments, the blood seal housing isattached to the catheter during the catheter placement steps. In suchembodiments, the housing forms a portion of a connector to whichsyringes and tubing sets may be attached. In other preferredembodiments, the blood seal housing is distinct from but attached to aconnector.

[0016] The blood seal of the present invention provides a self-closingseal through which an object such as a needle, wire, or cannula may bemoved. In certain preferred embodiments, the blood seal allows removalof an introducer needle from a vascular access device. In suchembodiments, a portion of the introducer needle is disposed within theslit or hole in the elastic plug. After venipuncture and theintroduction of the catheter into the patient's blood vessel, the userwithdraws the needle through the blood seal by pulling on a finger grip.After the needle is withdrawn, the biasing element squeezes the elasticplug, closing the hole or slit.

[0017] In other preferred embodiments, the introducer needle is attachedtot a wire, a portion of which is disposed within the slit or hole inthe elastic plug. After proper placement of the catheter, the userwithdraws the wire and the needle through the blood seal by pulling afinger grip. As described above, the biasing element forces the hole orslit closed after withdrawal of the wire and needle.

[0018] From the foregoing, it will be appreciated that a spring-biasedseptum may be used anytime a needle, cannula, wire, or other similarobject must pass through a seal. The present invention is especiallyuseful in controlling blood leakage during the placement and use ofvascular catheters. Thus, the problems related to blood leakage to theambient environment are substantially reduced. The present inventionalso provides a device that is simple and inexpensive to operate, andmay be used without significant modification of conventional cathetersand tubing sets.

[0019] These and other objects and advantages of the invention willbecome apparent upon reading the following detailed description andappended claims, and upon reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more fully understand the manner in which theabove-recited advantages and objects of the invention are obtained, amore particular description of the invention briefly described abovewill be rendered by reference to specific embodiments thereof which areillustrated in the appended drawings. Please take note that theembodiments illustrated in the drawings are merely illustrative.

[0021]FIG. 1 is a perspective view of one embodiment of a vascularaccess device incorporating the blood seal having a spring-biased septumof the present invention.

[0022]FIG. 2 is a perspective view of the spring-biased septum after theneedle has been withdrawn.

[0023]FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 2.

[0024]FIG. 4 is a cross-sectional view of the spring-biased septum priorto removal of the needle.

[0025]FIG. 5 is a longitudinal cross-sectional view of the blood sealprior to removal of the needle.

[0026]FIG. 6 is a partially cut-away plan view of a second embodiment ofa vascular access device incorporating the blood seal having aspring-biased septum of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The present invention can be best understood by reference to thedrawings where like parts are designated with like numerals throughout.One embodiment of a vascular access device incorporating the blood sealhaving a spring-biased septum of the present invention is generallydesignated 10 in FIG. 1. As mentioned above, the vascular access device10 allows for the placement of a catheter in a patient and subsequentremoval of the introducer needle while maintaining a blood seal at theproximal end of the catheter. This allows a medical professional tointroduce a catheter into a patient's blood vessel and remove theintroducer needle without the need to be concerned about blood leakage.

[0028] As illustrated in FIG. 1, the vascular access device 10 includesa catheter 12. The catheter 12 has a distal end 14, a proximal end 16,and an internal lumen 18. A needle 20 having a sharpened end 22 isslidably mounted within the internal lumen 18 of the catheter 12, suchthat the sharpened end 22 of the needle protrudes a short distancebeyond the distal end 14 of the catheter 12. The sharpened end 22 allowsa medical professional to puncture the blood vessel of a patient,creating an access site and facilitating the introduction of the distalend 14 of the catheter 12 into the blood vessel. The distal end 14 ofthe catheter 12 is tapered, allowing dilation of the access site as thedistal end 14 of the catheter 12 is introduced into the blood vessel.

[0029] The needle includes a distal opening 24, a notch-like opening 26,and a lumen 30. The lumen 30 permits fluid to flow between the distalopening 24 and the notch-like opening 26. As can be seen in FIG. 1, thenotch distance (that is, the distance between a proximal end of thenotch and an opening in the distal end of the needle) is less than thelength of septum 52.

[0030] The needle is provided with a proximal end 28 attached to afinger grip 34. The needle 20 extends coaxially through the internallumen 18 of the catheter, passes through a blood seal 40 disposed withina branched connector 42, and is attached to the finger grip 34, suchthat after the introduction of at least part of the catheter 12 into theblood vessel, the needle 20 may be withdrawn from the access site bypulling the finger grip 34 in the direction indicated by arrow A,minimizing the risk of injury to the blood vessel.

[0031] The branched connector 42 includes a housing 44 and an internalchannel 46 through the housing 44. Disposed within and substantiallyblocking the internal channel 46 is a spring-biased septum 50. Thehousing 44, internal channel 46, and spring-biased septum 50 form ablood seal.

[0032]FIG. 2 shows a perspective view of the spring-biased septum 50,which includes a dumbbell-shaped elastic plug 52. The elastic plug 52may be constructed of a biocompatible elastomer. In certain preferredembodiments, the elastic plug 52 is constructed of polyisoprene orlatex. The elastic plug 52 has an annular groove 54 in which a biasingelement 56 is disposed. In the embodiment shown in FIGS. 1 and 2, thebiasing element 56 is a C-shaped spring. The biasing element 56 may beconstructed of a resilient material. In certain preferred embodiments,the biasing element 56 is constructed of a metal or a metal alloy. Thebiasing element 56 may, for example, be constructed of spring steel.

[0033] The elastic plug 52 also includes a slit 58 through which theneedle 20 passes. It will be appreciated that the slit 58 may bereplaced by any of a number of equivalent elements, such as a hole orchannel through the elastic plug 52. Prior to use, a portion of theneedle 20 is disposed within the slit 58. After the needle 20 iswithdrawn, the slit 58 closes to prevent blood leakage.

[0034]FIG. 3 shows a cross sectional view of the spring-biased septum 50after the needle has been withdrawn. The elastic plug 52, biasingelement 56, and slit 58 are illustrated. From this view, it will beappreciated that the biasing element 56 compresses a portion of theelastic plug 52, keeping the slit 58 closed with a predictable force.

[0035]FIG. 4 shows a cross-sectional view of the spring-biased septum 50prior to removal of the needle 20. The needle 20, elastic plug 52,biasing element 56, and slit 58 are illustrated. This Figure illustratesthe manner in which the needle 20 penetrates the spring-biased septum 50through the slit 58.

[0036]FIG. 5 shows a longitudinal cross-sectional view of the blood seal40 prior to withdrawal of the needle 20 through the spring-biased septum50. The housing 44, internal channel 46, and spring-biased septum 50,which includes the elastic plug 52, the annular groove 54, and thebiasing element 56 are illustrated.

[0037] Returning to FIG. 1, the vascular access device 10 includes meansfor attaching conventional tubing sets and syringes. The branchedconnector 42 is attached to a tube 60, which is attached to a femaleadaptor 62. The female adaptor 62 permits removable attachment ofsyringes or other connectors. The embodiment of the vascular accessdevice 10 shown in FIG. 1 also includes an injection piece 64 attachedto the female adaptor 62. When the distal end 14 of the catheter 12 isin the blood vessel of a patient, medications may be injected via theinjection piece 64. It will be appreciated that other attachment means,such as threaded connectors and luer locks, are well known in the artand may be used with the present invention.

[0038] In operation, the user grips the vascular access device 10 by thebranched connector 42 (shown in FIG. 1) and punctures the blood vesselof a patient with the sharpened end 22 of the needle 20, facilitatingthe introduction of at least part of the distal end 14 of the catheter12 into the patient's blood vessel. The notch-like opening 26 allows theuser to monitor the placement of the needle 20. Blood flashback throughthe distal opening 24, into the lumen 30 of the needle 20, and out thenotch-like opening 26 verifies blood vessel puncture.

[0039] After proper placement of the needle 20 and the distal end 14 ofthe catheter 12 into the patient's blood vessel, the needle 20 iswithdrawn to prevent inadvertent damage to the blood vessel. The userwithdraws the needle 20 by pulling on the finger grip 34, which isattached to the proximal end 28 of the needle 20, in the direction ofarrow A. The sharp tip 22 of the needle 20 is withdrawn through thespring-biased septum 50. The biasing element 56 forces the slit 58 toclose, preventing blood leakage. The user may then discard needle 20,which is still attached to finger grip 34, in a container designed fordisposal of blood-contaminated sharps or as otherwise might beappropriate.

[0040] Removal of the needle 20 leaves the distal end 14 of the catheter12 in the patient's blood vessel. The user may then introduce a sourceof fluids or inject medications via the female adaptor 62 or injectionpiece 64. The means of connecting sources of fluids and medications tothe types of connector shown are well known in the art. Fluids andmedications flow into the tube 60, through the branched connector 42 andcatheter 12, and into the blood vessel of the patient.

[0041] A second embodiment of a vascular access device incorporating thespring-biased septum of the present invention is generally designated110 in FIG. 6. The vascular access device 110 includes a catheter 112having a distal end 114 and a proximal end 116. A needle 120 having asharpened end 122 is slidably mounted within the catheter 112, such thatthe sharpened end 122 of the needle protrudes a short distance beyondthe distal end 114 of the catheter 112. It will be appreciated that theneedle 120 may incorporate openings as described above that permit theuser to monitor placement of the needle 120. The sharpened end 122allows a medical professional to puncture the blood vessel of a patient,creating an access site and facilitating the introduction of the distalend 114 of the catheter 112 into the blood vessel. The distal end 114 ofthe catheter 112 is tapered, allowing dilation of the access site as thedistal end 114 of the catheter 112 is introduced into the blood vessel.

[0042] The needle 120 is provided with a proximal end 128 attached to awire 132. At the opposite end of the wire 132 from the proximal end 128of the needle 120 is a finger grip 134, such that after the introductionof at least part of the catheter 112 into the blood vessel, the needle120 may be withdrawn from the access site by pulling the finger grip134, minimizing the risk of injury to the blood vessel. The needle iswithdrawn through a tube 136 and a branched connector 142, through ablood seal 140, and into a protective sheath 160. The protective sheath160 may be as described in U.S. Pat. No. 5,304,136 and functions toprotect the user from an inadvertent needle stick.

[0043] The blood seal 140 includes a housing 144 and an internal channel146. A spring-biased septum 150 is disposed within and substantiallyblocks the internal channel 146. The spring-biased septum 150 is formedas described above and includes an elastic plug 152 with an annulargroove 154. A biasing element 156 is disposed within the annular groove154. The elastic plug includes a slit 158. Prior to use, a portion ofthe wire 132 is disposed within the slit 158. After placement of aportion of the catheter 112 into the blood vessel of the patient, thewire 132 and needle 120 are withdrawn through the slit 158. The biasingelement 156 compresses a portion of the elastic plug 152, closing theslit 158 and preventing blood leakage.

[0044] The vascular access device 110 includes means for attachingconventional tubing sets and syringes. The branched connector 142includes a female adaptor 162, permitting removable attachment ofsyringes of other connectors. It will be appreciated that otherattachment means, such as threaded connectors and luer locks, are wellknown in the art and may be used with the present invention.

[0045] In operation, the user punctures the blood vessel of a patientwith the sharpened end 122 of the needle 120, facilitating theintroduction of at least part of the distal end 114 of the catheter 112into the patient's blood vessel. After proper placement of the needle120 and the distal end 114 of the catheter 112 the needle 120 iswithdrawn to prevent inadvertent damage to the blood vessel. The userwithdraws the needle 120 by pulling on the finger grip 134, which isattached to the wire 132, which, in turn, is attached to the proximalend 128 of the needle 120. The needle 120 is withdrawn from the catheter112, through the tube 136 and branched connector 142, through the bloodseal 140, and into the protective sheath 160. The user may then discardthe protective sheath 160.

[0046] Removal of the needle 120 leaves the distal end 114 of thecatheter 112 in the patient's blood vessel. The user may then introducea source of fluids or inject medications via the female adaptor 162.Fluids and medications flow through the branched connector 142, tube136, and catheter 112 and into the blood vessel of the patient.

[0047] In summary, the present invention provides a device whichcontrols the flow of blood during the steps involved in the insertion ofa catheter. The present invention provides a device which is inexpensiveand simple to operate. The blood seal of the present invention can alsobe used without significant modification of conventional catheters,needles, tubing sets and the like.

[0048] The invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

What is claimed and desired to be secured by Letters Patent is:
 1. Aseptum and needle assembly comprising: a needle having a proximal endand a distal end with an opening at the proximal end, wherein the needledefines a notch therein adjacent to the distal end, and wherein a notchdistance is defined as the distance between a proximal end of the notchand a distal end of the opening in the distal end of the needle; ahousing; and a septum disposed in the housing and having a lengthgreater than the notch distance, wherein the needle is slidinglydisposed within the septum.
 2. The septum and needle assembly of claim 1wherein a slit is disposed within the septum and the needle is slidinglydisposed within the slit.
 3. The septum and needle assembly of claim 1further comprising a tube attached to and in fluid communication withthe housing.
 4. The septum and needle assembly of claim 3 furthercomprising a female adapter attached to the tube.
 5. The septum andneedle assembly of claim 1 further comprising a biasing element operablyengaged to the septum, urging the septum to a closed condition.
 6. Theseptum and needle assembly of claim 5 wherein the biasing element is aC-shaped clip.
 7. The septum and needle assembly of claim 6 wherein theseptum has a dumbbell shape and the C-shaped clip is directly engaged tothe septum.
 8. A vascular access device including: a catheter; a housingin fluid connection with the catheter; a septum disposed within thehousing and having a length; a needle slidingly disposed with respect tothe catheter, the needle having a proximal end and a distal end with anopening at the proximal end, wherein the needle defines a notch thereinadjacent to the distal end, and wherein a notch distance is defined asthe distance between a proximal end of the notch and a distal end of theopening in the distal end of the needle; a finger grip attached to theneedle at its proximal end; wherein the length of the septum is greaterthan the notch distance.
 9. The vascular access device of claim 8wherein the septum includes an elastic plug disposed in the housing andhaving a proximal end, a distal end, an outside longitudinal surfaceextending between the proximal end and the distal end, and a slitdisposed longitudinally through the elastic plug.
 10. The vascularaccess device of claim 9 further comprising a biasing element disposedin the housing about the elastic plug and in contact with the outsidelongitudinal surface of the plug, wherein the biasing element is in asingle fixed location with respect to the housing and continuouslyexerts a biasing force on the plug.
 11. The vascular access device ofclaim 9 wherein said elastic plug further comprises an annular groovedisposed in the outer surface of the plug.
 12. The vascular accessdevice of claim 9 further comprising a biasing element disposed in thehousing about the elastic plug and in contact with the outsidelongitudinal surface of the plug, wherein the biasing element is in asingle fixed location with respect to the housing and continuouslyexerts a biasing force on the plug, wherein said elastic plug furthercomprises an annular groove disposed in the outer surface of the plugand wherein the biasing element is placed in contact with the annulargroove.
 13. A catheter assembly, comprising: a catheter; an adapterconnected to the catheter, the adapter defining a cavity therein; anelastic plug disposed in the adapter and defining a length, acircumference and a slit disposed longitudinally through the elasticplug; a biasing element disposed in the adapter about the elastic plugand in contact with the circumference at a permanently fixed position;and a removable needle extending through the slit, the needle having aproximal end and a distal end with an opening at the proximal end,wherein the needle defines a notch therein adjacent to the distal end,and wherein a notch distance is defined as the distance between aproximal end of the notch and a distal end of the opening in the distalend of the needle.
 14. The catheter assembly of claim 13 wherein thebiasing element exerts a radially directed compressive force against theoutside longitudinal surface of the elastic plug.
 15. The catheterassembly of claim 13 wherein the biasing element does not extendcompletely about the circumference.
 16. The catheter assembly of claim13 wherein the elastic plug is mounted to the adapter at a fixed axialposition.
 17. The catheter assembly of claim 13 wherein the biasingelement is a C-shaped clip.
 18. The catheter assembly of of claim 13wherein the elastomeric plug has a dumbbell shape.
 19. The catheterassembly of claim 13 further comprising a tube in fluid communicationwith the adapter and a finger grip attached to the needle at itsproximal end.
 20. The catheter assembly of claim 19 wherein the biasingelement is a c-shaped clip that does not extend completely about thecircumference of the elastic plug but does exerts a radially directedcompressive force against the outside longitudinal surface of theelastic plug.